Blood flow controlling apparatus

ABSTRACT

A blood flow controlling apparatus, which is configured to be implanted into a blood circulatory system of a patient, comprises an anchoring means, which is arranged to fix the position of the apparatus in the blood circulatory system, and a valve means being connected to the anchoring means. The valve means is configured to be arranged within the blood circulatory system and is configured to be extendable in a direction transverse to blood flow in order to make contact with native tissue when inserted in the blood circulatory system. The valve means is further configured to release said contact as a result of being exposed to blood flow in a permitted direction.

CROSS REFERENCE TO A RELATED PATENT APPLICATION

The present application claims priority to Swedish Patent ApplicationSerial No. 0500891-7, filed on Apr. 21, 2005, the disclosure of which isincorporated by reference herein in its entirety.

TECHNICAL FIELD

The present invention relates to a blood flow controlling apparatus,which is configured to be implanted into a blood circulatory system of apatient, and to a method for treatment of leaking heart valves.

BACKGROUND OF THE INVENTION

Heart valve disease is a very common problem. Each year, half a millionpeople in the world develop heart valve disease. 200,000 are too sick tobe treated, but the rest are treated. At present, the treatment of heartvalve disease consists of either heart valve repair or valvereplacements. Both methods require open-heart surgery, by the use oftotal cardiopulmonary by-pass, aortic cross-clamping and arrest of theheart. To certain groups of patients, open-heart surgery is particularlyhazardous. However, a less invasive method for repair of heart valves isconsidered generally advantageous.

Heart valve insufficiency may arise from a dilation of the valveannulus, whereby the leaflets of the heart valve are moved away fromeach other such that the area of coaptation is minimized or vanished.The area of coaptation is the area where the leaflets of heart valveslean against each other, thereby closing the valve opening sufficiently.Thus, an existing gap or incomplete area of coaptation between theleaflets creates a leak in the valve.

In U.S. Pat. No. 6,210,432, a less invasive method is proposed fortreating heart valve insufficiency. Here, a method is described fortreatment of mitral insufficiency without the need for cardiopulmonaryby-pass and opening of the chest and heart. The method uses a devicecomprising an elongate body having such dimensions as to be insertableinto the coronary sinus, which is a vein that substantially encirclesthe mitral orifice and annulus and drains blood from the myocardium tothe right atrium. The elongate body has two states, in a first of whichthe elongate body has a shape that is adaptable to the shape of thecoronary sinus, and to the second of which the elongate body istransferable from said first state assuming a reduced radius ofcurvature. Consequently, the radius of curvature of the coronary sinusis reduced. Due to the coronary sinus encircling the mitral annulus, theradius of the coronary sinus curvature as well as the circumference ofthe mitral annulus are reduced by the reduction of the radius of thecoronary sinus. Thus, the described method takes advantage of theposition of the coronary sinus being close to the mitral annulus, whichmakes repair possible by the use of current catheter-guided techniques.However, the described method is only useful in diseased valves wherethe reason for a valvular leak is caused by a dilation of the valveannulus.

For prolapsing leaflets, catheter-based methods have been presentedwhere the two leaflets of the mitral valve are attached to each other bymeans of a thread (Percutaneous Edge-to-Edge provided by EdwardsLifesciences Corporation of Irvine, USA) or a clip (Evalve Systemprovided by Evalve, Inc. of USA) creating a double opening with a shapelike a bow-tie in the valve.

In cases where these methods are not useful, the valve may need to bereplaced. Percutaneous replacement of heart valves are being developedfor the aortic and pulmonary valves by Percutaneous Valve Technologies,Inc., now owned by Edwards Lifesciences Corporation and by CoreValveS.A. of Paris, France. NuMED, Inc. of New York, USA deliver a valvedesigned by Dr. Bonhoeffer for sole use in the pulmonary valve position.In all these devices, copies of normal human valves with three cusps aresewn from Glutaraldehyde-treated calf or horse pericardium tissue orbovine jugular vein tissue and mounted inside a stent. The stents fromEdwards Lifesciences and NuMED are made of stainless steel and need tobe dilated by a balloon, whereas the valve from CoreValve is mountedinside a self expanding stent of Nitinol. These devices from EdwardsLifesciences, NuMED and CoreValve will hereinafter be denoted stentedvalves. The stented valve is placed in the position of the valve it issupposed to replace and dilated, thereby pushing the leaflets and anycalcified tissue away and thereby completely eliminating the remainingfunction of the valve leaflets. However, the stented valves are onlyuseful in circular orifices such as the pulmonary and the aortic valves.

For the mitral valve and the tricuspid valve, no artificial valve has sofar been presented for percutaneous placement. The main reason for nothaving access to percutaneously implantable valves in the tricuspid andin the mitral valve position is that the valve annulus is oval and thevalve opening has a slit-like shape in case of a diseased mitral valveand triangular shape in case of a diseased tricuspid valve. The knownstented valves are fixed to the valve annulus by means of frictioncaused by pressure from the stents towards the surrounding tissue in thevalve opening. If the known stented valves with round circumference areintroduced into the oval mitral annulus with a leaking area of slit-likeshape, there will be wide open areas causing a severe leak, so calledparavalvular leak, between the implanted device and the annulus. Inaddition, the tissue is too weak to allow a good fixation in thetricuspid and mitral orifices. Further, if a known stented valve isintroduced in the mitral valve orifice, it would also create a block inthe outflow of the aortic valve.

The known stented valves also have limitations in use for the pulmonaryvalve. The known stented valves are not suited to be implanted inchildren or growing juveniles, since they do not permit growths of thevalve annulus. However, the most severe drawback with the known stentedvalves is the size of the device when mounted in delivery systems beforeimplant. Mounting the valve inside a stent creates a huge diameter ofthe device catheter. The present devices are 7 to 9 mm in diameter,which is a huge diameter considering that the catheter is to beintroduced through puncture holes in vessels through the skin and guidedthrough sometimes severely calcified vessels, most of them having thesame size as the device, to the target area. The diameter of suchdevices is half and half caused by the stent and the valve, which eachis 3-4 mm thick.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a device and method fortreatment of leaking heart valves, wherein the treatment may beperformed on any heart valve. It is a further object of the invention toprovide a device and method that may be used without the need for openheart surgery or stopping the heart.

These and other objects of the invention are accomplished by a bloodflow controlling apparatus and a method according to the independentclaims.

Thus, the invention provides a blood flow controlling apparatus, whichis configured to be implanted into a blood circulatory system of apatient. The apparatus comprises an anchoring means, which is arrangedto fix the position of the apparatus in the blood circulatory system,and a valve means being connected to the anchoring means. The valvemeans is configured to be arranged within the blood circulatory systemand is configured to be extendable in a direction transverse to bloodflow in order to make contact with native tissue when inserted in theblood circulatory system. The valve means is further configured torelease said contact as a result of being exposed to blood flow in apermitted direction.

The blood flow controlling apparatus according to the invention mayadvantageously be used for treating a leaking heart valve. The valvemeans of the apparatus is arranged to make contact with surroundingtissue for closing the valve and to release the contact for opening ofthe valve. The valve means may be arranged for making contact with heartvalve tissue, such as leaflet tissue. While having contact with theleaflet, an area of coaptation between the valve means and the nativeleaflet is established. In the area of coaptation, backflow through thevalve may be prohibited. The introduction of the valve means in anorifice of a heart valve therefore introduces a further leaflet whichcooperates with the native valve leaflets. Thereby, the apparatus isarranged according to an entirely new concept conserving and utilizingthe remaining function of the leaflets of the diseased native valve.

The valve means may be configured to contact tissue in the area ofcoaptation such that the valve means seals against native tissue toprevent blood flow past the valve means when the valve means extends inthe direction transverse to blood flow.

The feature that the valve means is configured to be extendable in adirection transverse to blood flow should be construed as the valvemeans being moveable to increase its extension in the directiontransverse to blood flow and not necessarily that the valve means willextend entirely in this direction. Thus, the valve means is able to movebetween a closed state, wherein it extends sufficiently in the directiontransverse to blood flow for preventing blood flow past the valve means,and an open state, wherein it extends primarily in a direction along theblood flow.

Further, the valve means may be oversized such that the valve means isarranged to overlap with native tissue when extending in the directiontransverse to blood flow. This strengthens the seal between the valvemeans and the tissue.

Since the valve means is arranged to close the leak in a regurgitatingheart valve by contacting and overlapping native valve tissue, theapparatus may be applied to a valve of any size and shape. As a matterof fact, the valve means of the apparatus can be oversized to such adegree that it will compensate for continuous deteriorations andshrinking of the native leaflets that is probable to occur especially inrheumatic heart disease. In the same way, an oversized valve means willallow growth of the native vessel or valve when implanted in children orstill growing juveniles.

Although the apparatus has been described above as cooperating withvalve tissue, it is contemplated that the apparatus may alternatively bearranged such that the valve means makes contact with an inner wall of avessel in which it is inserted, such as to introduce a valve functionwithin a vessel.

The apparatus may appropriately be inserted through the vascular systeminto a body and advanced to the heart or the great vessels close to theheart and to be subsequently deployed in or adjacent to the native heartvalve in order to treat any leak in a heart valve. Thus, there is noneed for opening the chest, stopping the heart or cutting or treating ofthe native valve tissue with advanced or demanding methods.

The valve means may present a contact surface comprising a contact areato make contact with native tissue, wherein the contact surface isarranged to extend such as to face blood flow from the permitteddirection. Thus, blood flow from the permitted direction will hit thecontact surface, providing a force on the valve means. This will pressthe valve means to release contact with tissue and allow blood flow pastit.

The apparatus may further comprise a spacer for providing a distancebetween the anchoring means and the valve means. The spacer may bearranged in the form of an elongate connecting means which connects theanchoring means to the valve means and provides an axial spacing betweenthe anchoring means and the valve means. Consequently, the apparatusseparates the valve means from the anchoring means, providing a smalldiameter of the apparatus, since the diameter of the anchoring means isnot superposed on the diameter of the valve means. The diameter of theapparatus may typically be 3-4 millimetres. This is very useful forintroduction of the apparatus, since it may be introduced through asmall puncture hole into the body. This makes the surgical procedureless invasive. Further, the anchoring means will not be arranged in theorifice of the native valve, whereby a much larger valve opening ispermitted and blood flow is facilitated through the valve.

The valve means may be attached to the connecting means as to strivetowards extending in the transverse direction to the connecting means.This implies that the valve means has an inherent strive towards makingcontact with a valve leaflet or a vessel wall when implanted in thepatient. The valve means will then need to be exposed to a force toprevent extending in the transverse direction. Such force may beprovided by blood flow in the allowed direction. As a result, thefunction of the valve means to allow blood flow in a forward directionand prevent blood flow in a backwards direction may be accomplished bythe inherent strive. Thus, no outside control of the valve means will beneeded to achieve this function. In fact, the valve means may bearranged such that blood flow in the backwards direction pushes thevalve means towards the native heart valve leaflets or a vessel wall tomake contact with the valve leaflets or vessel wall. Thus, backflow mayinitially aid in extending the valve means in the transverse direction.

The valve means may be arranged on the connecting means. According toone embodiment, the valve means is arranged symmetrically around theconnecting means. This implies that the valve means will act identicallyaround the circumference of the connecting means in order to closeagainst the native valve leaflet or the vessel wall. As a result, theplacement of the connecting means and the anchoring means is not verycritical for ensuring that the valve means will completely seal bloodflow through the valve or the vessel by making contact with the nativevalve leaflet or the vessel wall over its entire circumference. Further,as mentioned above, the valve means may be over-sized such that thediameter of the valve means, when extending transversely to theconnecting means, is larger than the jet of leaking blood or larger thanthe diameter of the vessel in which it is placed. This ensures that thevalve means will seal the vessel properly when making contact with thevessel wall, even when the connecting means is not exactly centrallypositioned in the valve or the vessel. However, the apparatus may bedesigned such that at least part of the connecting means is flexibleallowing the valve means to center itself to the center of the bloodflow.

The valve means may in its open state be configured to have a largerextension along the direction of blood flow than a native valve in itsopen state. This implies that the valve means may be arranged to reachand make contact with native valve leaflets that are extending toabnormal positions. This ensures that a coaptation will be achieved alsoto areas of the native valve that are prolapsing towards the atria, asituation that often occurs in diseases with redundant native valvematerial. Also, coaptation will be achieved with leaflets restrained byshortened chordae tendinae.

The valve means may comprise a flap, which is moveable between an openposition where it extends along the connecting means and a closedposition where it extends in a transverse direction to the connectingmeans.

The flap may comprise an attachment end, which forms an attachment ofthe flap to the connecting means in a longitudinal position of theconnecting means. The flap may further comprise a contact end, which isarranged to make contact with native tissue. The flap may be hingedlymoveable around the attachment position between its open position andclosed position, where the contact end makes contact with tissue.

The contact end may be connected to the connecting means by means ofcontrol strings. The control strings may prevent the flap from turningover to extend along the connecting means in the opposite longitudinaldirection. If the flap would turn over, no contact with the native valveor the vessel wall would occur, and consequently blood may regurgitatethrough the valve means.

The flap may form an attachment to the connecting means extending alonga longitudinal direction of the connecting means. The flap will thenhave a secure attachment to the connecting means to avoid the need ofcontrol strings for preventing the flap to be turned over.

The sealing of the valve means to the native valve leaflet or the vesselwall may be accomplished by various embodiments. In one embodiment, theflap extends around the entire circumference of the connecting means.The flap may be homogenous or comprise several subsections, which mayform an umbrella- or parachute-like shape.

In another embodiment, the valve means comprises several flaps. Theflaps may overlap each other to properly seal the valve or vessel whenextending to make contact with the native valve leaflet or the vesselwall. Thus, no backflow is allowed between the flaps. As an alternative,adjacent flaps may tightly contact each other to prevent leakage betweenthe flaps.

The flaps may be strengthened at an end which is attached to theconnecting means. The strengthened base may act to prevent the flapsfrom turning over.

The flap or flaps may preferably be made of biological tissue, such asanimal tissue treated with Glutaraldehyde or similar solutions. Theanimal tissue may originate from heart valve, blood vessels orpericardial tissue, which is normally used for producing artificialbiological heart valves. However, the flaps may also or alternatively bemade of a synthetic material, such as polyurethane, polyvinyl orpolytetrafluoroethylene (PTFE), or a shape memory material, such asNitinol or shape memory polymers.

One advantageous feature of the blood flow controlling apparatus is theanchoring means for fixing the position of the apparatus in the bloodcirculatory system. The anchoring means prevents migration of the valvemeans away from a correct position inside a heart valve or a vessel.During systole of the heart rhythm, there is a high pressure gradientbetween ventricle and atrium and, during diastole of the heart rhythm,there is a high pressure gradient between the aorta and left ventricleand between the pulmonary artery and the right ventricle. Therefore, astrong fixation of the apparatus is needed to avoid migration of thevalve means.

Depending on the fixation site for the anchoring means, the valve meansmay be arranged on either side of the anchoring means such that theallowed blood flow may be directed from the anchoring means to the valvemeans or vice versa.

Further, depending on the fixation site in the blood circulation systemof the patient, there are a number of embodiments for the anchoringmeans. The valve means may be arranged to be placed at a mitral valve, atricuspid valve, a pulmonary valve or an aortic valve. The apparatus maytherefore be used to treat a leak in any of these valves. Alternatively,the valve means may be arranged in an arterial vessel or a venous vesselfor introducing a valve function in the artery or the vein, which mayreplace the function of a diseased heart valve. The anchoring means maybe arranged to engage an arterial vessel wall, a venous vessel wall, theatrial septum, the interventricular muscular septum, a muscularventricular wall, or an atrial wall. The anchoring means is fixed in aposition that is suitable for the placement of the valve means.

The anchoring means may comprise an expandable element for engaging walltissue. This implies that the anchoring means fixes the position of theapparatus by securing the apparatus to wall tissue. The expandableelement may be tube-shaped. The anchoring means may then be used to fixthe position of the apparatus to a wall of a vessel by engaging thevessel wall along the entire circumference of the tube-shaped element.The anchoring means may be arranged to fix the position of the apparatusto a vessel in or adjacent to the heart where the valve means is to bearranged in a regurgitating heart valve. The expandable element may be astent forming a tube from a mesh of struts. The expandable element maybe a conventional vascular stent, which is normally used for supportingvessel walls during dilation treatment of vascular disease.

The connecting means is attached to the anchoring means for connectingthe valve means to the anchoring means. The connecting means may e.g. beconnected to either end of the anchoring means, such as to extendthrough the anchoring means towards the valve means or as an extensionfrom the anchoring means towards the valve means. The connecting meansmay be attached to one or more, preferably two, stent struts.Preferably, the attachment is a seamless continuation of the strutmaterial into the connecting means. Such attachment could be achieved ifthe anchoring means and the connecting means are constructed out of thesame piece of material, for instance by laser cutting. Otherwise, theattachment could be made by means of welding.

The expandable element may alternatively comprise a plurality of springsarranged to engage with opposite sides of a wall of a heart atrium. Theanchoring means may thus fix a position inside a heart atrium byengaging opposite walls of the heart atrium.

In an alternative embodiment, the anchoring means comprises adisk-shaped element, which is arranged for engaging a tissue wall. Inthis embodiment, the valve means and the disk-shaped element of theanchoring means are arranged on opposite sides of the tissue wall andthe connecting means extends through the tissue wall. The position isfixed by the disk-shaped element abutting and engaging the tissue wall.

The anchoring means may comprise another disk-shaped element and whereinthe disk-shaped elements are connected by a penetration part forengaging opposite sides of a tissue wall. In this embodiment, thedisk-shaped elements fix the position of the apparatus by abutting andengaging opposite sides of the tissue wall.

The anchoring means comprising one or more disk-shaped elements may beused for fixation to e.g. the interatrial septum or another heart wall,where the valve means is to be arranged in the mitral or tricuspidvalve.

According to a further alternative embodiment, the anchoring meanscomprises hooks arranged for penetrating wall tissue. Such an anchoringmeans may also be used for fixation to e.g. the interatrial septum oranother heart wall, where the valve means is to be arranged in themitral or tricuspid valve.

According to another alternative embodiment, the anchoring meanscomprises a plurality of arms arranged for engaging chordae tendinae.According to yet another alternative embodiment, the anchoring meanscomprises clips arranged for engaging papillary muscles. Theseembodiments of the anchoring means may also be used for fixation to e.g.the interatrial septum or another heart wall, where the valve means isto be arranged in the mitral or tricuspid valve.

The anchoring means may be made of a shape memory material, such asNitinol or a shape memory polymer. This implies that the anchoring meansmay be self-expandable to assume its preprogrammed shape. However,ordinary stainless steel, stainless spring steel or any other metalmight be used. The connecting means would preferably be made of similarmaterial as the anchoring means.

The apparatus may comprise two connecting means extending from theanchoring means in different directions, wherein valve means areattached on each connecting means. The apparatus may then be used fortreating two malfunctions in the body simultaneously. For example, theapparatus may be arranged such that one valve means is placed in themitral valve and one valve means is placed in the tricuspid valve forsimultaneous treatment of these valves. The anchoring means may comprisetwo disk-shaped elements arranged to engage opposite sides of theinteratrial septum or the interventricular septum and connecting meansmay extend in opposite directions from the anchoring means towards themitral and tricuspid valves, respectively.

The connecting means may be arranged to assume a programmed shape withinthe blood circulatory system. In this case, the connecting means may bemade of a shape memory material, e.g. Nitinol, allowing the connectingmeans to be straight during insertion and to resume a pre-programmed,curved shape exactly fitting the calculated track from the fixationpoint to the correct position of the valve means. This facilitatesinsertion and placing of the apparatus in the blood circulatory system.

In an alternative embodiment, the connecting means comprises a pluralityof segments arranged in sequence, wherein the interrelationship betweenadjacent segments is controllable. This implies that the connectingmeans may be designed in a very flexible manner by the segments beingable to flexibly move in relation to each other. The connecting meansmay thus e.g. allow an operator to manipulate it for centering the valvemeans in a stream of blood created by the leak in the native valve.

The connecting means may further comprise a locking mechanism forlocking the position of adjacent segments to each other. Thus, whenplaced in an appropriate position, each segment may then be locked toeach other for fixating the shape of the connecting means and thus theposition of the valve means. The locking mechanism may comprise atension wire arranged extending through the sequential segments. Thewire may be locked under tension for fixating the shape of theconnecting means. The locking mechanism may further comprise a tap forengaging the tension wire to lock the form of the tension wire throughthe sequential segments. Thus, the tap locks the wire under tension tofix the shape of the connecting means.

The connecting means may have a longitudinal groove or channel forreceiving a guide wire. The connecting means may e.g. be tubular orU-shaped for allowing a guide wire to pass through the connecting means.This implies that the connecting means may be introduced into thepatient by sliding over a guide wire.

The connecting means may further comprise a disengaging means forreleasing the valve means from the anchoring means. This implies that avalve means, which may have lost its treating function over time, may bereplaced without the need to replace the entire apparatus.

According to another aspect of the invention, there is provided a kitfor controlling blood flow in a blood circulatory system of a patient.The kit comprises a blood flow controlling apparatus as described aboveand a delivery system for carrying the blood flow controlling apparatusto a desired position in the blood circulatory system.

The kit may provide a package to a surgeon who is about to introduce ablood flow controlling apparatus into a patient. Thus, the kit providesboth an implant which may be used for treating the patient and adelivery system which may be used for inserting the implant.

The anchoring means of the blood flow controlling apparatus may bemounted in the delivery system during storage, whereas the valve meansof the blood flow controlling apparatus may be mounted in a containerwith appropriate storage fluid. Where the valve means is made ofbiological material, it will need to be stored in a storage fluid inorder not to be destroyed during storage. The valve means may bearranged such that the operator may pull the valve means inside thedelivery system just prior to insertion into the patient.

The valve means may be disconnected from the anchoring means duringstorage. This implies that the valve means is stored in a separatecontainer and may be attached to the rest of the blood flow controllingapparatus just prior to insertion into the patient.

The kit may further comprise a guide wire for guiding insertion of thedelivery system to the desired position through the vascular system ofthe patient. The delivery system may also comprise a guiding catheterwhich is arranged to be pushed over the guide wire to the desiredposition. Thus, the blood flow controlling apparatus may be inserted tothe desired position through the vascular system of the patient.

According to a further aspect of the invention, there is provided amethod for controlling blood flow in a blood circulatory system of apatient. The method comprises inserting an artificial valve means to adesired position in the blood circulatory system; arranging theartificial valve means in the desired position such that the valve meansextends in a direction transverse to blood flow for making contact withheart valve tissue or vessel wall tissue and the valve means releasessaid contact when being exposed to blood flow in a permitted direction;and fixing the position of the artificial valve means by attaching ananchoring means in the blood circulatory system, said anchoring meansbeing connected to the artificial valve means at an axial distancetherefrom. The implanted artificial valve means may thus block backflowin a leaking heart valve and allow only forward flow in the valve. Theanchoring means may be arranged at an axial distance from the valvemeans provided by an elongate spacer. Consequently, the valve means isspaced from the anchoring means, enabling insertion into the bloodcirculatory system through a small diameter, since the diameter of theanchoring means is not superposed on the diameter of the valve means.

The inserting may be performed through the vascular system by means of acatheter. According to this method, the valve means may be inserted andfixated by means of an instrument being inserted through the vascularsystem of a patient providing a low-invasive treatment method that onlyrequires a needle puncture of the skin, thereby getting access to thevascular system, without the need of any surgery or anaesthesia. Theaccess to the vascular system may be achieved through the venous orarterial system of the patient.

As an alternative, the valve means may be inserted and fixated through asmall surgical access from outside the chest, entering the pericardialspace and inserting the apparatus through the ventricular or atrial wallby guidance of direct vision and/or x-ray and ultrasound imaging.

As another alternative, the valve means may be inserted and fixatedthoracoscopically, by means of an endoscope or a surgical robot, usingan access from outside the chest, entering the pericardial space andinserting the device through the ventricular or atrial wall by guidanceof vision through the endoscope or the robot equipment.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in further detail by way of exampleunder reference to the accompanying drawings.

FIG. 1 is a schematic view of a partial cross-section of the heartindicating its general anatomy.

FIG. 2 a is a schematic view of a blood flow controlling apparatusaccording to a first embodiment of the invention with a valve means ofthe apparatus being in an open state allowing blood flow.

FIG. 2 b is a schematic view of a blood flow controlling apparatusaccording to a first embodiment of the invention with a valve means ofthe apparatus being in a closed state preventing blood flow.

FIG. 2 c shows different cross-sections of the blood flow controllingapparatus in expanded and compressed states.

FIGS. 3 a-3 d are schematic views of the blood flow controllingapparatus showing different embodiments of an expanding element foranchoring the apparatus.

FIGS. 4 a-4 f are schematic views of the blood flow controllingapparatus showing other embodiments of an anchoring means.

FIG. 4 g is a schematic view of a blood flow controlling apparatuscomprising two anchoring means.

FIGS. 5 a-i are schematic views of a connecting means of the blood flowcontrolling apparatus.

FIG. 5 j is a schematic view of a connecting means providing detachmentof the valve means from the anchoring means.

FIGS. 6 a-c are schematic views of different embodiments of a valvemeans of the blood flow controlling apparatus.

FIGS. 7 a-f are views of a further embodiment of the valve means.

FIGS. 8 a-f are schematic views of a mitral valve indicating a valvemeans of a blood flow controlling apparatus according to the inventionbeing inserted for treating a leak in the mitral valve.

FIGS. 9 a-c are schematic views of a tricuspid valve indicating a valvemeans of a blood flow controlling apparatus according to the inventionbeing inserted for treating a leak in the tricuspid valve.

FIGS. 10 a-c show a blood flow controlling apparatus being inserted inthe aorta for treatment of a leaking aortic valve.

FIGS. 11 a-d show different embodiments of a blood flow controllingapparatus being inserted in the pulmonary artery.

FIG. 12 shows blood flow controlling apparatuses being inserted in thesuperior vena cava and the inferior vena cava.

FIGS. 13 a-k are schematic views of a heart showing differentembodiments of the blood flow controlling apparatus being inserted inthe mitral valve and tricuspid valve, respectively.

FIGS. 14 a-h are schematic views showing a delivery system carrying andreleasing the blood flow controlling apparatus.

FIGS. 15 a-20 e are schematic views illustrating methods for insertingthe blood flow controlling apparatus into a patient.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

Referring to FIG. 1, the general anatomy of a heart 1 will be described.Blood is lead through the superior vena cava 2 and the inferior venacava 4 into the right atrium 6 of the heart 1. The tricuspid valve 8controls blood flow between the right atrium 6 and the right ventricle15. The tricuspid valve 8 is closed when blood is pumped out from theright ventricle 15 to the lungs. During this period, blood is filledinto the right atrium 6. Thereafter, the tricuspid valve 8 is opened tofill the right ventricle 15 with blood from the right atrium 6. Freeedges of leaflets of the tricuspid valve 8 are connected via chordaetendinae 10 to papillary muscles 12 for controlling the movements of thetricuspid valve 8. Blood from the right ventricle 15 is pumped throughthe pulmonary valve 20 to the pulmonary artery 22 which branches intoarteries leading to each lung. Blood from the lungs are lead throughpulmonary veins 28 into the left atrium 26 of the heart 1. The mitralvalve 30 controls blood flow between the left atrium 26 and the leftventricle 17. The mitral valve 30 is closed when blood is pumped outfrom the left ventricle 17 to the aorta 34 and the arteries of the body.During this period, blood is filled into the left atrium 26. Thereafter,the mitral valve 30 is opened to fill the left ventricle 17 with bloodfrom the left atrium 26. Free edges of leaflets of the mitral valve 30are connected via chordae tendinae 11 to papillary muscles 13 forcontrolling the movements of the mitral valve 30. Blood from the leftventricle 17 is pumped through the aortic valve 32 into the aorta 34which branches into arteries leading to all parts of the body.

The function of the heart 1 may be impaired by any of the heart valvesnot functioning properly. The heart valves may lose their ability toclose properly due to e.g. dilation of an annulus around the valve or aleaflet being flaccid causing a prolapsing leaflet. The leaflets mayalso have shrunk due to disease, e.g. rheumatic disease, and therebyleave a gap in the valve between the leaflets. The inability of theheart valve to close will cause a leak backwards, so calledregurgitation, through the valve, whereby the function of the heart 1will be impaired since more blood will have to be pumped through theregurgitating valve.

Referring now to FIGS. 2 a-2 c, an apparatus 42, which may be used intreatment of a regurgitating heart valve, will be generally described.The apparatus 42 is arranged to be implanted into a patient forproviding a permanent or at least long-term treatment. The apparatus 42comprises a valve means 52, which is transferable between an open state,as shown in FIG. 2 a, allowing blood flow past the valve means 52, and aclosed state, as shown in FIG. 2 b, preventing blood flow past the valvemeans 52. The valve means 52 is arranged to make contact withsurrounding tissue in its closed state for sealing a blood flow path. Asillustrated in FIGS. 2 a-b, the valve means 52 has a greater radialextension in the closed state than in the open state for making contactwith tissue. The valve means 52 will release the contact in its openstate to allow blood flow, wherein the valve means 52 in its open statewill be arranged within the path of the blood flow. Differentembodiments of the valve means 52 will be described in further detailbelow with reference to FIGS. 6-7.

The apparatus 42 further comprises an anchoring means 54. The anchoringmeans 54 is arranged to fix the position of the apparatus 42 in apatient. The anchoring means 54 is arranged to engage with tissue forfixing the position of the apparatus 42. Different embodiments of theanchoring means 54 will be described in further detail below withreference to FIGS. 3-4.

The apparatus further comprises a connecting means 46, which connectsthe valve means 52 with the anchoring means 54. The connecting means 46provides a spacing between the anchoring means 54 and the valve means52. This implies that the apparatus 42 may be arranged in an elongateform and may be arranged in a small diameter. This facilitates insertionof the apparatus 42 into the patient, since the apparatus 42 may beinserted through a small incision. In FIG. 2 c, the cross-section of theapparatus 42 at the anchoring means 54 and at two positions in the valvemeans 52 are shown below a side view of the apparatus 42. Thecross-section of the apparatus 42 when implanted is shown immediatelybelow the view of the apparatus 42. Further below, the cross-section ofthe apparatus 42 when compressed during insertion is shown. The valvemeans 52 and the anchoring means 54 are inserted in sequence andtherefore the diameter of the device will not be an accumulation of thediameters of the valve means 52 and the anchoring means 54. Instead, theapparatus 42 may be compressed to a very small diameter as shown in FIG.2 c. Further, the connecting means 46 provides a possibility to fix theposition of the valve means 52 by the anchoring means 54 engaging anappropriate site in the vicinity of the desired position of the valvemeans 52. The anchoring means 54 is not intended to engage tissue at theexact positioning of the valve means 52. The connecting means 46 alsoprovides a surface or position, to which the valve means 52 is attached.

The apparatus 42 is arranged to be inserted in a minimally invasivemanner into the patient. The apparatus 42 may be inserted endoscopicallythrough a small diameter or be guided through the vascular system of thepatient by means of a catheter-based technique. In the latter case, theapparatus 42 may be introduced into the vascular system through apuncture in e.g. the groin or the neck of the patient. The apparatus 42may be held in a compressed state during insertion for providing assmall diameter as possible of the apparatus 42. Further, the apparatus42 may comprise a channel or groove for receiving a guide wire throughthe apparatus 42, such that the apparatus 42 may be guided to thecorrect position sliding on the guide wire.

Referring now to FIGS. 3-4, different embodiments of the anchoring meanswill be described. The anchoring means may be realised in any mannerproviding engagement with tissue for fixing the position of theapparatus. The anchoring means may thus comprise hooks, barbs, spikes orany other means for engaging with or partially or wholly penetrating atissue portion. The anchoring means may also or alternatively comprisean element which is arranged for contacting a tissue portion for fixingthe position. This element may be accomplished in a tubular or ring-likeform for engaging an inner wall of a structure in the blood circulatorysystem, such as a vessel wall or an atrium wall. The element engages theinner wall to create contact along a circumference of the element.Preferably, the element is pushed towards the inner wall by an internalstrive to expand its radius. The anchoring means may, as a furtheralternative, be arranged to contact a tissue portion at an opposite sideof a tissue wall to the position of the valve means. The anchoring meansmay thus form a contact surface with the tissue portion which is largerthan a penetration hole through the tissue portion for fixing theposition of the apparatus.

As shown in FIG. 3 a-c, the anchoring means 54 may comprise a tubularexpandable element 55, which is arranged to make contact with a bloodvessel wall along its circumference. The tubular element 55 may be astent. The stent 55 may be self-expandable having an internal strive toexpand into contact with the vessel wall. Alternatively, the stent 55may be expanded by means of an external force, such as an inflation of aballoon from inside the stent 55. The stent 55 may be formed of threadsor struts that constitute a zig-zag pattern. The stent 55 may beinserted into the patient in a compressed shape having a small radiusand be expanded when placed in the desired position. As shown in FIG. 3a, the connecting means 46 branches into two arms 58 which are attachedto diametrically opposite positions of the stent 55. As shown in FIG. 3b, the connecting means 146 may alternatively branch into two arms 158which are attached to struts of the stent 55 which are close to eachother or immediately adjacent each other. Further, as shown in FIG. 3 c,the connecting means 246 may be arranged to assume a prebent shape suchas to provide a connection between an anchoring means 54 and a valvemeans 52, which are not to be placed in line with each other within thepatient. The connecting means 246 may alternatively be flexible suchthat it may be forced to a desired shape within the patient by usinge.g. a preshaped catheter. As a further alternative, the connectingmeans 246 may be flexible such that it centers itself within the bloodflow in which it is located.

As shown in FIG. 3 d, the anchoring means 154 may alternatively comprisea plurality of threads or struts 155 that are resilient or spring-likesuch that they have an inherent strive towards assuming a shape havingcontact with an inner wall of an atrium over a substantial length of thethread 155. The thread 155 may be elliptic or circular for contactingthe atrium wall. The anchoring means 154 may comprise a plurality ofthreads 155 such that a large contact area is created with the atriumwall. The threads 155 may be symmetrically distributed such that contactis symmetrically achieved with the atrium wall.

In FIGS. 3 a-d, the anchoring means is arranged on an “inflow” side ofthe valve means, that is the valve means permits blood flow from thedirection of the anchoring means past the valve means. This is suitablewhen the valve means is to be arranged in the mitral or tricuspid valveand the anchoring means is to be arranged in a blood vessel or a heartatrium for fixing the position of the apparatus. The embodiments of theanchoring means shown in FIGS. 4 a-f, which will be described furtherbelow, are arranged on an “outflow” side of the valve means, that is thevalve means permits blood flow past the valve means towards theanchoring means. This is suitable e.g. when the valve means is to bearranged in the mitral or tricuspid valve and the anchoring means isarranged to fix the position of the apparatus by engaging ventriculartissue.

As shown in FIG. 4 a, the anchoring means 254 may comprise a disk-shapedelement 255 to be arranged in contact with a heart wall portion, such asa ventricular wall or interventricular septum. The connecting means 46will extend through the heart wall and the disk-shaped element 255 willprevent the anchoring means 254 from migrating through the heart wall.The anchoring means 254 may further comprise a hook, barb or the likefor engaging the heart wall. The disk-shaped element 255 may becompressed for insertion through the heart wall and may assume itsdisk-shape when a compressing force is released.

As shown in FIG. 4 b, the anchoring means 354 may comprise two or morehooks 355 for engaging chordae tendinae. The connecting means 346branches off into essentially transversal branches extending to therespective hooks 355. The hooks 355 are arranged to capture chordaetendinae within the hooks 355 for fixing the position of the apparatus42.

As shown in FIG. 4 c, the anchoring means 454 may comprise a pluralityof clips 455 for engaging papillary muscles. The clips 455 are arrangedto grab around the papillary muscles for fixing the position of theapparatus 42. Again, the connecting means 446 branches off into branchesextending transversally and even backwards to one or more clips 455,respectively.

As shown in FIG. 4 d, the anchoring means 554 may comprise a pluralityof disk-shaped or bar-shaped elements 555 arranged to engage a valveannulus. The connecting means 546 branches off into branches extendingbackwards such that the anchoring means 554 may be arranged inengagement with a valve annulus where the valve means 52 is arranged inthe valve. The engagement with the valve annulus may be accomplished bytwo disk-shaped or bar-shaped elements 555 engaging opposite sides ofthe annulus. The anchoring means 554 may then further comprise aconnection 557 between the disk-shaped elements 555, wherein theconnection 557 is arranged to extend through the valve annulus. Theconnection 557 may further comprise projections 559, which may be usedfor fixing the position of one of the disk-shaped elements 555 along theconnection 557. The disk-shaped element 555 may then be pushed or forcedover the projection 559 and be held in this position. Thus, the distancebetween the two disk-shaped elements 555 is adjustable to fit thethickness of the valve annulus and to thereby attach the apparatus tothe valve annulus.

As shown in FIGS. 4 e-f, the anchoring means arranged on an “outflow”side of the valve means may comprise a stent 55 as described above withreference to FIGS. 3 a-c. As shown in FIG. 4 e, the connecting means 46may branch into two arms 58 which are attached to diametrically oppositepositions of the stent 55 and are attached to an end of the stent 55which is closest to the valve means 52. As shown in FIG. 4 f, the twoarms 58 of the connecting means 46 may alternatively be attached to anend of the stent 55 which is farthest away from the valve means 52. Thisembodiment may be arranged in a very compact form with the valve means52 being arranged close to the anchoring means 54.

As shown in FIG. 4 g, the apparatus 42 may comprise two anchoring means54, 254, which are arranged on an “inflow” and “outflow” side of thevalve means 52, respectively. The two anchoring means 54, 254 maycooperate to securely fix the position of the apparatus 42 within thepatient.

The anchoring means may be made of a shape memory material, such asNitinol or a shape memory polymer. This implies that the anchoring meansmay be self-expandable to assume its preprogrammed shape. This isespecially suitable where the anchoring means comprises an element to beexpanded within the patient. However, ordinary stainless steel,stainless spring steel or any other metal might be used. The connectingmeans could be made of similar material as the anchoring means. Theconnecting means may then be an extension of the anchoring means withoutthe need of any welding or attachment point between the connecting meansand the anchoring means.

The connecting means may be realised as an elongate body providing aspacer and connection between the valve means and the anchoring means.The connecting means may have branches for extending to different partsof an anchoring means in order to provide a more secure connectionbetween the anchoring means and the connecting means or in order tocreate a connection between separate anchoring means. The connectingmeans may e.g. have a round or flat cross-section. The connecting meansmay be tubular or have a groove, e.g. U- or C-shaped, for receiving aguide wire during insertion of the apparatus 42. The connecting meansmay alternatively be formed from a solid material. The connecting meansmay as a further alternative be made of threads or struts forming a gridof zig-zag or scissor-shaped thin material. The connecting means maystill be hollow or present a groove while being shaped as a grid. Theconnecting means may be arranged in a flexible material or in a shapememory material such that the connecting means may be fitted to aspecific track after being inserted in the body. As a furtheralternative, the connecting means may be formed from a plurality ofsequentially arranged segments, whose mutual relationship may becontrolled or adjusted.

Referring now to FIGS. 5 a-i, a segment-based embodiment of theconnecting means will be described. In FIG. 5 a, an apparatus 42 isshown with a connecting means 46 being arranged between the anchoringmeans 54 and the valve means 52. In FIG. 5 b, a portion of theconnecting means 46 marked with circle B in FIG. 5 a, is shown ingreater detail. The connecting means 46 comprises sequential connectingsegments 100. In FIG. 5 c, two connecting segments 100 are indicated ineven greater detail. The connecting segments 100 comprise a head 102,which may e.g. be spherically shaped, and an end 104 with a recess 105corresponding to the shape of the head 102, such that the recess 105 mayreceive a head 102. The recess 105 is slightly larger than the head 102to allow the head 102 to be rotated within the recess for adjusting themutual relationship of adjacent segments 100. The head 102 comprises asmall protrusion or knob 106 and the end 104 comprises a small notch 108for receiving the protrusion 106. When the protrusion 106 is positionedin the notch 108, the segments 100 are aligned. The protrusion 106 maybe pushed out of the notch 108 by applying a small force to theconnecting means 46. There may be multiple protrusions 106 and notches108 on the head 102 and end 104, respectively, so that the head 102 andend 104 may engage in multiple different relationships in order to lockthe connecting segments 100 in different desired angles. The segments100 further comprise a channel 110 for receiving a locking wire. Bylocking the shape of the locking wire when extending through thesegments 100, the mutual relationships of the segments 100 is locked, aswill be further described below. In FIG. 5 d, a front segment 113 of theconnecting means 46 is shown. The front segment 113 comprises an end 104similar to the ends 104 of the other segments 100. The front segment 113comprises a blind bore 114 in its end 104. The locking wire 112 isreceived in the blind bore 114 and attached to the front segment 113within the bore 114. The front segment 113 provides a non-flexible partof the connecting means 46 and may have a longer longitudinal extensionthan the other segments 100. The front segment 113 is arranged at theend of the connecting means 46 closest to the valve means 52.

In FIG. 5 e, a rear segment 116 of the connecting means 46 is shown. Therear segment 116 comprises a head 102 similar to the heads 102 of theother segments 100. The rear segment 116 also comprises a channel 110for receiving the locking wire 112. The rear segment 116 also comprisesat its end a locking mechanism 101 for locking the shape of the lockingwire 112. The rear segment 116 also comprises welding or fixation points118 for attaching the rear segment 116 to the anchoring means 54 or toarms 58, 158 or branches of the connecting means 46, which in turn areattached to the anchoring means 54.

The locking mechanism 101 will now be further described with referenceto FIGS. 5 f-h. In FIG. 5 f, the parts of the locking mechanism 101 areshown. The locking mechanism comprises an arm 120, which is a rotatablyattached to the end segment 116 in a rotation point 122. The arm 120 maybe attached to the end segment 116 by means of a pin extending through ahole in the arm 120 and engaging the end segment 116. The arm 120 has aprotrusion 124, which may be rotated into engagement with grooves 126 inthe locking wire 112. The protrusion 124 may be e.g. wedge-shaped asshown in FIG. 5 f. An adjustment wire 128 may be attached and detachedto the locking wire 112. The adjustment wire 128 may be arranged toextend outside the patient for providing control of the position of thelocking wire 112 from outside the patient during insertion of theapparatus 42. The locking wire 112 and the adjustment wire 128 maycomprise corresponding notches 133, 134 and grooves 130, 132 forproviding an attachment between the wires. Operation of the lockingmechanism 101 is shown in FIGS. 5 g-h. The adjustment wire 128 isarranged in a fixation tube 136, which covers the attachment between theadjustment wire 128 and the locking wire 112 for preventing detachmentof the wires. When the fixation tube 136 is pulled backwards orwithdrawn from the patient, the adjustment wire 128 can be detached fromthe locking wire 112. In FIG. 5 g, the locking arm 120 is shown inengagement with the locking wire 112 locking the shape of the lockingwire 112. As shown in FIG. 5 h, the fixation tube 136 can also be movedforward to rotate the locking arm 120, so that the wedge-shapedprotrusion 124 is forced out of the groove 126 and thereby the lock isopened. The mutual relationships of the segments 100 of the connectingmeans 46 can then be adjusted again. When the locking wire 112 isstretched and locked instead, the friction between the spherical-shapedrecess 105 in a segment and the head 102 of the adjacent segment willfix the segments in a certain position relative to each other.

Orientation of the segments 100 in relation to each other may in oneembodiment, as shown in FIG. 5 i, be made by means of a preshapedcatheter 135 that force the segments 100 to line up according to theshape of the catheter 135 before the segments 100 are locked relative toeach other. The catheter 135 may have any shape to mimic the desiredtrack of the connecting means 46. The catheter 135 may have a shapememory such that the catheter 135 may be activated to assume its shapewhen the apparatus 42 has been fixed in the body.

Another embodiment for orientating the segments 100 in relation to eachother is to attach threads 135′ to the segments 100. By pulling in thethreads 135′, at least one segment 100 can be steered to the correctposition. When all segments 100 have been correctly placed, the segments100 may be locked relative to each other. The thread 135′ may be doubleforming a loop that engages a hook or loop on the segment 100. When thesteering is completed, the thread 135′ may be pulled out.

As shown in FIG. 5 j, the connecting means 46 may provide a possibilityto disengage the valve means 52 from the anchoring means 54. The valvemeans 52 may in time suffer structural damage or calcification and maytherefore need to be replaced. By disengaging the implanted valve means52, there is only a need to replace the valve means 52. The connectingmeans 46 may therefore comprise a lock 137 for enabling detachment ofthe valve means 52 from the anchoring means 54. Where an embodiment ofthe connecting means 46 as shown in FIGS. 5 a-j is used, the lock 137may e.g. be provided in the front segment 103. In FIG. 5 j, the lock 137is enlarged showing one possible embodiment. The lock 137 has a maleportion 138 with a threaded winding 139, which is fitted into a femaleportion 140 with a threaded groove 141. Thus, the male portion 138 maybe screwed on or off the female portion 140 for engaging or releasingthe lock. It should be appreciated that numerous other embodiments ofthe lock are possible. For example, the lock may be formed from a hookengaging a loop or a pin engaging a bore.

Referring now to FIGS. 6-7, different embodiments of the valve meanswill be described. Generally, the valve means is arranged to seal thenative heart valve or blood vessel in which it is placed in order toprevent backflow in the valve or the vessel. The valve means istherefore oversized so that it will certainly contact and seal againstthe leaflets of the native valve or against the wall of the vessel. Thevalve means will further provide a surface facing forward flow in thenative heart valve or the vessel, wherein the surface is arranged insuch a manner that when exposed to blood flow in the forward direction,the blood flow will force the valve means to open.

According to a first embodiment shown in FIG. 6 a, the valve means 52comprises a flap 44 which symmetrically encircles the connecting means46. The flap 44 is attached to the connecting means 46 around its entirecircumference in a longitudinal attachment point 90 forming a fluidtightattachment around the connecting means 46. The flap 44 is hinged in theattachment point 90 such that it is moveable between an open positionwhere it extends mainly along the connecting means 46 and a closedposition, as shown in FIG. 6 a, where it extends in a mainly transversedirection to the connecting means 46. The flap 44 has a contact surface92 which faces the forward flow in the native heart valve or the vesseland which is arranged to contact the leaflets of the native heart valveor the vessel wall in the closed position of the flap 44. When movinginto the closed position, the flap 44 will move towards increasinglyextending in a transverse direction to the connecting means 46. Thecontact surface 92 will then come into contact with the leaflets of thenative heart valve or the vessel wall before the flap 44 extends in afully transverse direction to the connecting means 46. The flap 44 willtherefore contact the leaflets of the native heart valve or the vesselwall in a coaptation area 94 of the contact surface 92 corresponding toa short distance along the leaflets of the native heart valve or thevessel and the boundary of the coaptation area 94 forming a closedcircumferential shape such that coaptation is achieved around the entirevalve means 52. This oversizing of the flap 44 also implies that theconnecting means 46 will not need to be precisely centrally positionedin the native heart valve or the vessel.

The contact surface 92 has a rim 96 at the end which comes in contactwith the leaflets of the native heart valve or the vessel wall. The rim96 is strengthened by enforcement strings 53 connecting the rim 96 witha fixation point 98 on the connecting means 46. The enforcement strings53 stabilize the shape of the flap 44 in the closed position. Theenforcement strings 53 may be an integrated part of the flap 44 or theymay be attached to the flap 44 by e.g. gluing or a knot. The enforcementstrings 53 also prevent the flap 44 from turning over, i.e. to extend inthe opposite direction along the connecting means 46 from the attachmentpoint 90. If the flap 44 would turn over it would no longer function toallow forward flow nor preventing backflow past the valve means 52.

The flap 44 of the valve means 52 has an internal strive to assume theshape of the closed position. When inserted and released from arestraining cover, the valve means 52 will open like a parachute, makecontact with the leaflets of the native heart valve or the vessel walland form a valve that only allows flow in one direction.

The second embodiment of the valve means is shown in FIG. 6 b. Thisvalve means 152 comprises a flap 144, which is divided into subsections145 by means of flap enforcement parts 147. This gives the flap 144 amore stable umbrella-like or parachute-like shape and therefore fewerenforcement strings 153 are needed. In fact, the enforcement strings 153may be completely omitted if the flap enforcement parts 147 aresufficiently strong or rigid to prohibit a turning over of the flap 144.The enforcement strings 153 are attached to the flap 144 at theinterface between two adjacent subsections 145 and connect the flap 144to a fixation point 198. As for the first embodiment, the flap 144 isattached symmetrically around an attachment point 190 of the connectingmeans 46 and provides a contact surface 192 with a coaptation area 194.

In the third embodiment shown in FIG. 6 c, the valve means 252 comprisesseveral flaps 244. The flaps 244 are attached to a common attachmentposition 290 around the connecting means 46. Each flap 244 has a contactsurface 292 with a coaptation area 294 and the flap 244 is moveable toput the coaptation area 294 of the contact surface 292 in contact withthe leaflets of the native heart valve or the vessel wall. The flaps 244are broadening towards the coaptation area 294. Further, the flaps 244are overlapping and arranged as the leaves of a hibiscus flower so as toform a tight seal between them when extending to make contact with theheart valve or the vessel wall. The flaps 244 further have astrengthened base 296 close to the attachment position 290. Thestrengthened base 296 will prevent the flap 244 from turning over due tobackflow in the heart valve or the vessel.

In the fourth embodiment shown in FIGS. 7 a-d, the valve means 352comprises several flaps 344 which are arranged side-by-side encirclingthe connecting means 46. As indicated in FIG. 7 c showing a perspectiveview of the valve means 352, each flap 344 comprises a contact surface392 with a coaptation area 394. The flaps 344 are wedge-formed with thenarrow end towards the connecting means 46 and the broad end arranged tomake contact with the native heart valve or the vessel wall. Asindicated in FIG. 7 a showing a cross section of the valve means 352when inserted in a native heart valve or a vessel, adjacent flaps 344extend along each other and are arranged close together such thatadjacent surfaces present respective coaptation areas 392, which will bein close contact with each other to prevent leakage between the flaps344. In FIG. 7 a, the valve means 352 is depicted in the closed positionin which it is arranged to make contact with the native heart valve or avessel wall. When blood flows forward through the open valve means 352it will take the shape depicted in FIGS. 7 b and 7 d. Now thewedge-shaped flaps 344 are pressed against the connecting means 46 bythe force of the blood stream and the valve means 352 is open. Thisembodiment of the valve means 352 would be especially effective inirregular shaped orifices, as for instance in severe calcified nativeheart valves.

In FIGS. 7 e and 7 f, attachment of the flaps 344 to the connectingmeans 46 is shown. The flaps 344 are attached to the connecting means 46in an attachment line 390 along a longitudinal direction of theconnecting means 46. The flap 344 may be attached to the connectingmeans 46 over the entire length of the flap 344 (see FIG. 7 e) or over apart of the length of the flap 344 (see FIG. 7 f). The longer attachmentline 390 makes enforcement strings unnecessary.

As shown in FIGS. 7 b and 7 d, the flaps 344 will collapse towards theconnecting means 46 when exposed to blood flow in the forward direction.The flap material is very thin to allow the flap 344 to contract towardsthe connecting means 46 when exposed to the blood flow.

The flap or flaps of the valve means according to any embodiment arepreferably made of biological tissue, which has been treated withglutaraldehyde or any tanning or fixation medium. The biological tissuemay e.g. be tissue from pericardium or heart valve of an animal.

The valve means may alternatively be made of polymers, such aspolyurethane, polyvinyl, polyethylene, polyethylene terephthalate (PET),polytetrafluoroethylene (PTFE), or rayon. However, the flap or flaps mayalso be made of a shape memory material, such as Nitinol or shape memorypolymers, whereby an ultrathin flap having a thickness of 3-4 μm may beformed.

The valve means may be covered with active drugs. One such drug would beheparin, for prevention of clot formation in the blood circulationsystem of the patient. Another drug would be nitric oxide, which alsoprevents clot formation, and also a combination of heparin and nitricoxide is possible.

Referring now to FIGS. 8-12, the use of an apparatus 42 for controllingblood flow in a patient will be generally described. The apparatus 42may be used for treating a regurgitating heart valve, as illustrated inFIGS. 8-9, or for controlling blood flow through an artery or a vein, asillustrated in FIGS. 10-12.

FIGS. 8 a-f illustrate the treatment of a regurgitating mitral valve 30.The mitral valve 30 comprises a posterior leaflet 35 and an anteriorleaflet 37. The leaflets 35, 37 move for opening and closing the mitralvalve 30.

In FIG. 8 a, a regurgitating mitral valve 30 is shown, where theposterior and anterior leaflets 35, 37 are not able to close the valveproperly. The valve 30 has a leak 31 in a central position of the valve30. In FIG. 8 b, the mitral valve 30 with an implanted apparatus 42 isshown. The valve means 52 of the apparatus 42 is placed in the leak 31such that a coaptation area 94 between the valve means 52 and theleaflets 35, 37 is created for closing the leak 31. The valve means 52in its closed state makes contact with the leaflets in a short distancealong the contact surface 92 such that a cylindrical surface constitutesthe coaptation area 94 such that a tight seal is created. In FIG. 8 c,another shape of the valve means 52 is shown for treatment of the leak31. In this case, the valve means 52 has a rectangular or an oval shapein its closed state, which may also effectively form a coaptation area94 for tightly sealing the leak 31. In FIGS. 8 d and 8 e, a mitral valve30 having a leak 31 positioned asymmetrically in the valve 30 is shown.The apparatus 42 is implanted such that the valve means 52 is centrallypositioned within the leak 31 for forming a coaptation area 94 in orderto tightly seal the leak 31. In FIG. 8 f, a schematic cross-section ofthe heart 1 is shown illustrating the placement of the valve means 52within the mitral valve 30. The valve means 52 has a greater extensionalong the blood flow between the left atrium 26 and the left ventricle17 than the native mitral valve 30. This implies that the valve means 52may effectively contact prolapsing leaflets that extend into the leftatrium 26 and that the valve means 52 may form a tight coaptation area94 to many different shapes of leaks in the mitral valve 30. Such agreat extension of the valve means 52 along the blood flow also impliesthat the valve means 52 effectively may contact leaflets restrained byshortened chordae tendinae 11 inside the left ventricle 17.

FIGS. 9 a-c illustrate the treatment of a regurgitating tricuspid valve8. The tricuspid valve 8 comprises a medial leaflet 9 a, a posteriorleaflet 9 b and an anterior leaflet 9 c. The leaflets 9 a, 9 b, 9 c movefor opening and closing the tricuspid valve 8.

In FIG. 9 a, a regurgitating tricuspid valve 8 is shown, where theleaflets 9 a, 9 b, 9 c are not able to close the valve properly. Thevalve 8 has a leak 19 in a central position of the valve 8. In FIG. 9 b,the tricuspid valve 8 with an implanted apparatus 42 is shown. The valvemeans 52 of the apparatus 42 is placed in the leak 19 such that acoaptation area 94 between the valve means 52 and the leaflets 9 a, 9 b,9 c is created for closing the leak 19. The valve means 52 in its closedstate makes contact with the leaflets in a short distance along thecontact surface 92 such that a cylindrical surface constitutes thecoaptation area 94 such that a tight seal is created. In FIG. 9 c, aschematic cross-section of the heart 1 is shown illustrating theplacement of the valve means 52 within the tricuspid valve 8. The valvemeans 52 has a greater extension along the blood flow between the rightatrium 6 and the right ventricle 15 than the native tricuspid valve 8.This implies that the valve means 52 may effectively contact prolapsingleaflets that extend into the right atrium 6 and that the valve means 52may form a tight coaptation area 94 to many different shapes of leaks inthe tricuspid valve 8. Such a great extension of the valve means 52along the blood flow also implies that the valve means 52 effectivelymay contact leaflets restrained by shortened chordae tendinae 10 insidethe right ventricle 15.

FIGS. 10 a-c illustrate use of the apparatus 42 for controlling bloodflow through the aorta, which may be used for treatment of aregurgitating aortic valve 32. The apparatus 42 may replace the functionof the aortic valve 32.

As shown in FIG. 10 a, the anchoring means 54 of the apparatus 42 may beplaced in the aorta 34 for fixing the position of the apparatus 42. Theanchoring means 54 comprises a stent 55, which is expanded in contactwith the aorta 34 for fixing the position of the apparatus 42. Theanchoring means 54 is preferably arranged on the “outflow” side of thevalve means 52 such that the valve means 52 may be arranged close to theposition of the aortic valve 32. The valve means 52 is placed upstreamto a position where coronary arteries 39 branches off from the aorta 34.Thus, the valve means 52 may effectively control blood flow from theleft ventricle 17 to all parts of the body. The valve means 52 isarranged to make contact with the walls of the aorta 34 in a coaptationarea 94 for preventing blood flow past the valve means 52. The valvemeans 52 releases the contact and opens when exposed to blood flow fromthe left ventricle 17. In FIG. 10 b, a specific embodiment of the valvemeans 52 is illustrated. The valve means 52 comprises recesses 97corresponding to the openings of the coronary arteries 39 to the aorta.Thus, the valve means 52 may be arranged at least partly overlapping theposition in the aorta where the coronary arteries 39 branches off fromthe aorta. The valve means 52 will prevent blood flow between the aorta34 and the left ventricle 17 when the valve means 52 is closed, leavingthe coronary arteries 39 open to the aorta 34 in order to permit bloodflow to the heart muscle. Instead of having recesses 97 in the flap 44,the valve means 52 may be positioned with the rim 96 arranged just belowthe coronary artery opening in the aorta 34. Thus, blood flow to thecoronary arteries during diastole may occur undisturbed even when thevalve means 52 is in the closed position. As a matter of fact, the valvemeans 52 may be positioned partly inside the left ventricle 17 such thatthe flap 44 is leaning on the anterior leaflet 37 of the mitral valve30. As shown in FIG. 10 c, a further stent 41 may be arranged in theaorta 34 at the position of the aortic valve 32. This stent 41 may pressthe malfunctioning aortic valve 32 and any calcification thereof againstthe wall of the aorta 34, such that the blood flow control of the valvemeans 52 of the apparatus 42 is not disturbed by the native aortic valve32 if this is calcified. This stent 41 may be a covered or at leastpartially covered stent 41. The covered stent 41 may be positionedpartly inside the left ventricle 17 in order to be arranged upstream ofthe coronary arteries 39. The covered stent 41 thereby provides achannel from inside the left ventricle 17 into the aorta 34.

FIGS. 11 a-d illustrate use of the apparatus 42 for controlling bloodflow through the pulmonary artery 22, which may be used for treatment ofa regurgitating pulmonary valve 20. The apparatus 42 may replace thefunction of the pulmonary valve 20.

As shown in FIG. 11 a, the anchoring means 54 of the apparatus 42 may beplaced in the pulmonary artery 22 for fixing the position of theapparatus 42. The anchoring means 54 comprises a stent 55, which isexpanded in contact with the pulmonary artery 22 for fixing the positionof the apparatus 42. The anchoring means 54 is arranged on the “outflow”side of the valve means 52 such that the valve means 52 may be arrangedclose to the position of the pulmonary valve. The valve means 52 isplaced to effectively control blood flow from the right ventricle 15 tothe lungs. The valve means 52 is arranged to make contact with the wallsof the pulmonary artery 22 in a coaptation area 94 for preventing bloodflow past the valve means 52. The valve means 52 releases the contactand opens when exposed to blood flow from the right ventricle 15. InFIG. 11 b, another positioning of the anchoring means 54 is illustrated.The anchoring means 54 is placed in the main left branch 24 of thepulmonary artery 22. The connecting means 46 may in this embodiment havea preprogrammed shape to adapt to the curve of the artery between theposition of the valve means 52 and the anchoring means 54. As shown inFIG. 11 c, the anchoring means 54 may alternatively be arranged on the“inflow” side of the valve means 52. The anchoring means 54 fixes theposition of the apparatus 42 in a position of the pulmonary artery 22close to the right ventricle 15. The valve means 52 may then be placedin a position in the pulmonary artery 22 upstream of a position wherethe pulmonary artery 22 branches into the left and right pulmonaryarteries. Thus, the valve means 52 is still placed to effectivelycontrol the blood flow from the right ventricle to the lungs. As shownin FIG. 11 d, a further stent 43 may be arranged in the pulmonary artery22 at the position of the pulmonary valve 20. This stent 43 may pressthe malfunctioning pulmonary valve and any calcification thereof againstthe wall of the pulmonary artery 22, such that the blood flow control ofthe valve means 52 of the apparatus 42 is not disturbed by the nativepulmonary valve 20. As for the stent 41, the stent 43 may also be acovered or at least partially covered stent 43.

In FIG. 12, there is shown a blood flow controlling apparatus 42 beingpositioned in the superior vena cava 2 and another blood flowcontrolling apparatus 42 being positioned in the inferior vena cava 4.The valve means 52 is arranged to make and release contact with the wallof the superior vena cava 2 and the inferior vena cava 4, respectively,for opening and closing blood flow through the vessel. A valve means 52in the superior vena cava 2 or inferior vena cava 4 may be useful incases of congenital defects where it is impossible to place a valvemeans 52 in the pulmonary artery 22. Then, the valve means 52 mayinstead be placed upstream in the blood circulation system, such asshown in FIG. 12.

Referring now to FIGS. 13 a-k, the positioning and anchoring ofdifferent embodiments of the apparatus for placing the valve means inthe mitral or tricuspid valve will be described. The valve means isarranged in the mitral or tricuspid valve for improving the valvefunction as described above with reference to FIGS. 8-9. The apparatusmay be anchored in a number of different ways, as is shown in FIGS. 13a-k. Depending on how the apparatus is anchored, the anchoring means isdesigned in different ways. It will be appreciated by those skilled inthe art, that the apparatus may be designed in many other alternativeways for appropriately placing the valve means in a heart valve orwithin a blood vessel.

In FIG. 13 a, the apparatus 42 is arranged such that the valve means 52is placed in the tricuspid valve 8. The position of the apparatus 42 isfixed in the body by the anchoring means 54 being placed in the superiorvena cava 2 for engaging the wall of the vessel. An embodiment of theanchoring means 54 as shown in FIG. 3 b is used. The connecting means146 extends through the right atrium 6 between the superior vena cava 2and the tricuspid valve 8 for connecting the valve means 52 to theanchoring means 54. In FIG. 13 b, the apparatus 42 is arranged such thatthe valve means 52 is placed in the mitral valve 8. Now, an anchoringmeans 54 as shown in FIG. 3 c is used for engaging the wall of thesuperior vena cava 2. The connecting means 246 extends from the superiorvena cava 2, through the right atrium 6, penetrating the interatrialseptum 14 and through the left atrium 26 to the valve means 52 placed inthe mitral valve 30. The connecting means 46 may have a preprogrammedshape adapted to its extension between the superior vena cava 2 and themitral valve 30. Alternatively, the connecting means 46 may be flexiblefor allowing it to be appropriately shaped and thereafter locked in theappropriate shape.

In FIG. 13 c, an apparatus 42 as shown in FIG. 3 d is used for treatinga mitral valve 30. The anchoring means 154 is expanded to contact theinner wall of the left atrium 26 for fixing the position of theapparatus 42, while the valve means 52 is arranged in the mitral valve30. In FIG. 13 d, another way of using the apparatus 42 shown in FIG. 3b is shown. The anchoring means 54 is now arranged to make contact witha vessel wall in a pulmonary vein 28 and the connecting means 46 isarranged extending through the left atrium 26 to the valve means 52which is arranged in the mitral valve 30.

FIGS. 13 e-i illustrate different embodiments of the anchoring means 54for use when the valve means 52 is arranged in the mitral valve 30. Itwill be appreciated by those skilled in the art that these embodimentsmay be used instead for placing the valve means 52 in the tricuspidvalve 8. In FIG. 13 e, an apparatus as shown in FIG. 4 b is used. Theanchoring means 354 is arranged to engage the chordae tendinae 11 suchthat the chordae tendinae 11 are captured within the hooks 355 of theanchoring means 354 for fixing the position of the apparatus 42. In FIG.13 f, an apparatus as shown in FIG. 4 d is used. The anchoring means 554is arranged to engage the mitral valve annulus. The anchoring means 554is shown penetrating the valve annulus with disk-shaped elements 555engaging opposite sides of the valve annulus for fixing the position ofthe apparatus 42. Further, another disk-shaped element 555 is arrangedin contact with a ventricular side of the valve annulus for stabilizingthe apparatus 42 within the left ventricle 17. In FIG. 13 g, anapparatus 42 as shown in FIG. 4 c is used. The anchoring means 454 hasclips 455 which are arranged engaging the papillary muscles 13 forfixing the position of the apparatus 42. In FIGS. 13 h and 13 i, anapparatus 42 as outlined in FIG. 4 a is used. The anchoring means 254has a disk-shaped element 255 which is arranged in contact with a tissuewall. The valve means 52 and the anchoring means 254 are arranged onopposite sides of the tissue wall and the connecting means 46 penetratesthe tissue wall. The anchoring means 254 in contact with the tissue walltherefore fixes the position of the apparatus 42. However, in FIGS. 13 hand 13 i, the anchoring means 254 comprises another disk-shaped element255 such that the disk-shaped elements 255 engage opposite sides of thetissue wall for securely fixing the position of the apparatus 42. InFIG. 13 h, the anchoring means 254 is arranged to engage theinterventricular septum 16 and in FIG. 13 i, the anchoring means 254 isarranged to engage the left ventricle muscle wall 18.

FIGS. 13 j and 13 k illustrate an apparatus 42 being used forsimultaneously treating the mitral valve 30 and the tricuspid valve 8.The apparatus 42 comprises two valve means 52 being positioned in therespective native valves. The apparatus 42 comprises a connecting means46 connecting the two valve means 52. The connecting means 46 isarranged extending between the valves through the interventricularseptum 16 (as shown in FIG. 13 j) or the interatrial septum 14 (as shownin FIG. 13 k), respectively. Further, the apparatus 42 comprisesanchoring means 254 having disk-shaped elements 255 which are arrangedon opposite sides of the interventricular septum 16 or interatrialseptum 14, respectively, in order to engage tissue and fix the positionof the apparatus 42.

Referring now to FIGS. 14 a-h, a delivery system 500 for inserting theapparatus 42 into a patient will be described. As shown in FIG. 14 a,the delivery system 500 comprises a guide wire 508, which is firstintroduced into the patient extending to the position where theapparatus 42 is to be placed. The guide wire 508 thereafter provides aguiding path to the desired position within the patient. The deliverysystem 500 further comprises a delivery catheter 502, which is theoutermost part of the delivery system 500 within the vascular system ofthe patient. For the sake of clarity, the delivery catheter 502 is notshown in the following figures of the delivery system 500. The apparatus42 is guided to the position inside the delivery catheter 502. Thedelivery system 500 further comprises a restraining catheter 504. Thiscatheter 504 keeps the apparatus 42 in a compressed state duringdelivery. The delivery system 500 further comprises an inner tube 506which is arranged to slide on the guide wire to the desired position andpush the apparatus 42 in front of it.

Referring to FIGS. 14 b-d, deployment of an apparatus 42 will beindicated. In FIG. 14 b, the entire apparatus 42 is inside therestraining catheter 504. The valve means 52 is arranged distal to theanchoring means 54 in the restraining catheter 504, that is the valvemeans 52 is introduced into the patient in front of the anchoring means54. The restraining catheter 504 is retracted to release the restrain onthe valve means 52, as shown in FIG. 14 c. Thus, the valve means 52 isexpanded, while the anchoring means 54 is kept in a compressed state.The restraining catheter 504 is then further retracted, releasing theanchoring means 54, as shown in FIG. 14 d. Now, the entire apparatus 42is deployed.

Referring to FIGS. 14 e-g, another deployment of an apparatus 42 will bedescribed. In FIG. 14 e, the entire apparatus 42 is inside therestraining catheter 504. Now, the valve means 54 is arranged distal tothe anchoring means 52 in the restraining catheter 504. Again, therestraining catheter 504 is retracted to release the restrain on theanchoring means 54, as shown in FIG. 14 f. Thus, the anchoring means 54is expanded for fixing the position of the apparatus 42, while the valvemeans 52 is kept in a compressed state. The restraining catheter 504 isthen further retracted, releasing the valve means 52, as shown in FIG.14 g. Now, the entire apparatus 42 is deployed.

In FIG. 14 h, the delivery system 500 is shown in connection to anapparatus 42 having a connecting means 46 with a lock 137 for providinga possibility to detach the valve means 52 from the anchoring means 54.The detachment mechanism can be utilized for storage purposes. When thevalve means 52 are made of glutaraldehyde-treated biological tissue, thevalve means 52 can be stored in a liquid fluid while the rest of theapparatus 42 and delivery system 500 may be stored under dry conditions.When making ready for use, the valve means 52 that has been stored inliquid may be rinsed and thereafter connected to the anchoring means 54by attaching the male portion 138 of the lock 137 to the female portion140 of the lock 137. Thereafter the valve means 52 may be folded andretracted or pushed inside the restraining catheter 504 to make theentire apparatus 42 ready for insertion into a patient.

Referring now to FIGS. 15-20, methods for inserting an apparatus 42 intoa patient will be described.

Referring first to FIGS. 15 a-e, a method for inserting an apparatus 42for treatment of the tricuspid valve 8 will be described. In FIG. 15 a,a body of a patient is shown, indicating the heart 1 and access to theheart 1 via the vascular system. A puncture is made in the groin of thepatient for accessing the femoral vein 5, which leads to the inferiorvena cava 4 and further to the right atrium 6 of the heart 1. Anintroducer sheath 501 of the delivery system 500 is applied in thepuncture for providing an access tube into the femoral vein 5. The guidewire 508 of the delivery system 500 is lead into the right atrium 6 forproviding guidance of the apparatus 42 to the desired position. In FIG.15 b, another access route to the right atrium 6 is indicated. Apuncture is made in the neck of the patient for accessing the internaljugular vein 7 of the patient. The guide wire 508 is lead through theinternal jugular vein 7 to the superior vena cava 2 and into the rightatrium 6. The guide wire 508 is further introduced extending through thetricuspid valve 8 into the right ventricle 15. As shown in FIG. 15 c,the delivery catheter 502 is now introduced extending to the orifice ofthe tricuspid valve 8. For the sake of clarity, the delivery catheter502 will not be shown in the following FIGS. 15 d-e. Now, therestraining catheter 504 and the apparatus 42 is introduced over theguide wire 508 to the tricuspid valve 8. As shown in FIG. 15 d, therestraining catheter 504 is retracted so far that the valve means 52 isreleased inside the orifice of the tricuspid valve 8. The entiredelivery system 500 with the apparatus 42 may still be moved in theaxial direction to find the optimal position of the valve means 52 inthe orifice of the tricuspid valve 8. During this positioning, theeffect of the introduced valve means 52 may be controlled simultaneouslyby means of ultrasound. The restraining means 504 is thereafterwithdrawn further and finally from the body, as shown in FIG. 15 e.Hereby, the anchoring means 54 is deployed inside the superior vena cava2 and the apparatus 42 is completely deployed. The apparatus 42 has nowbeen implanted for providing permanent treatment of the tricuspid valve8. The inner tube 506, the delivery catheter 502 and the guide wire 508may now also be withdrawn.

Referring now to FIGS. 16 a-d, a method for inserting an apparatus 42for treatment of the mitral valve 30 will be described. In FIG. 16 a, anaccess route to the left atrium 26 is indicated. A puncture is made inthe neck of the patient for accessing the internal jugular vein 7 of thepatient. The guide wire 508 is lead through the internal jugular vein 7to the superior vena cava 2 and into the right atrium 6. The guide wire508 is further introduced through the interatrial septum 14 into theleft atrium 26 and further through the mitral valve 30 into the leftventricle 17. If the patient has a persistent foramen ovale, the guidewire 508 may instead be lead from the right atrium 6 through the foramenovale into the left atrium 26. As shown in FIG. 16 b, the deliverycatheter 502 is thereafter introduced over the guide wire 508 extendingto the orifice of the mitral valve 30. Again, the delivery catheter 502will not be shown in the following FIGS. 16 c-d. The restrainingcatheter 504 with the apparatus 42 is now introduced over the guide wire508 extending to the mitral valve 30. Thereafter, the restrainingcatheter 504 is retracted, as shown in FIG. 16 c, so that the valvemeans 52 is released inside the orifice of the mitral valve 30. Again,the entire delivery system 500 with the apparatus 42 may still be movedin the axial direction to find the optimal position of the valve means52 in the orifice of the mitral valve 30. The restraining catheter 504is thereafter withdrawn to release the anchoring means 54 and finallywithdrawn from the patient. As shown in FIG. 16 d, the anchoring means54 has been deployed inside the superior vena cava 2 and the apparatus42 is completely deployed.

Referring now to FIGS. 17 a-d, a method for inserting an apparatus 42for treatment of the pulmonary valve 20 will be described. In FIG. 17 a,an access route to the pulmonary artery 22 is indicated. A puncture ismade in the neck of the patient for accessing the internal jugular vein7 of the patient. The guide wire 508 is lead through the internaljugular vein 7 to the superior vena cava 2 and into the right atrium 6.The guide wire 508 is further introduced through the tricuspid valve 8,the right ventricle 15 and into the pulmonary artery 22. The restrainingcatheter 504 is introduced over the guide wire 508 and inside thedelivery catheter 502 to extend into the pulmonary artery 22, as shownin FIG. 17 b. The restraining catheter 504 is retracted, as shown inFIG. 17 c, so that the anchoring means 54 is released inside thepulmonary artery 22 for fixing the position of the apparatus 42. Therestraining catheter 504 is further retracted and withdrawn from thepatient. As shown in FIG. 17 d, the valve means 52 is deployed insidethe pulmonary artery 22 at the position of the pulmonary valve 20 andthe apparatus 42 is completely deployed. The same method may be used incase the anchoring means 54 is arranged on an “inflow” side of the valvemeans 52, as shown in FIG. 11 c, or when a stent 43 is arranged in thepulmonary valve position, as shown in FIG. 11 d. In the latter case, thestent 43 is first implanted at the position of the pulmonary valve 20.Thereafter, the apparatus 42 is inserted.

Referring now to FIGS. 18 a-d, a method for inserting an apparatus 42for treatment of the aortic valve 32 will be described. In FIG. 18 a, anaccess route to the aortic valve 32 is indicated. A puncture is made inthe neck of the patient for accessing the internal jugular vein 7 of thepatient. The guide wire 508 is lead through the internal jugular vein 7to the superior vena cava 2 and into the right atrium 6. The guide wire508 is further introduced through the interatrial septum 14 into theleft atrium 26, further through the mitral valve 30 into the leftventricle 17, and through the aortic valve 32 into the aorta 34.Alternatively, the route through a persistent foramen ovale might bechosen, as described above with reference to FIG. 16 a. The restrainingcatheter 504 and the apparatus 42 is introduced inside the deliverycatheter (not shown) such that the restraining catheter 504 extends intothe ascending aorta 33, as shown in FIG. 18 b. The valve means 52 islocated adjacent to the aortic valve 32 such that the rim 96 of thevalve means 52 is located just below the orifices of the coronaryarteries 39. Alternatively, the apparatus depicted in FIG. 10 b is used,wherein the valve means 52 comprises recesses 97 to fit the orifices ofthe coronary arteries 39. The restraining catheter 504 is retracted, asshown in FIG. 18 c, such that the anchoring means 54 is released insidethe ascending aorta 33 for fixing the position of the apparatus 42. Therestraining catheter 504 is further retracted and finally withdrawn fromthe patient. As shown in FIG. 18 d, the valve means 52 is deployedinside the aortic ostium and the apparatus 42 is completely deployed.

Referring now to FIGS. 19 a-d, another method for inserting an apparatus42 for treatment of the aortic valve 32 will be described. In FIG. 19 a,an access route to the aortic valve 32 is indicated. A puncture is madein the groin of the patient to access a femoral artery 38. A guide wire508 is passed through the femoral artery 38, the descending aorta 36 tothe ascending aorta 33 and into the left ventricle 17. Alternatively,other arteries can be used such as the subclavian artery 29. A guidewire 508 is introduced through the arteries to the ascending aorta 33,through the aortic valve 32 and into the left ventricle 17. In FIG. 19b, the guide wire 508 has been introduced through the subclavian artery29 into the aorta 34. The restraining catheter 504 and the apparatus 42are introduced inside the delivery catheter (not shown) such that therestraining catheter 504 extends into the ascending aorta 33. The valvemeans 52 is located adjacent to the aortic valve 32 with the rim 96 ofthe valve means 52 being located below the orifices of the coronaryarteries 39. As shown in FIG. 19 c, the restraining catheter 504 isretracted such that the valve means 52 is released inside the aorticvalve 32. Again, the entire delivery system 500 with the apparatus 42may still be moved in the axial direction to find the optimal positionof the valve means 52 at the aortic valve 32. The restraining catheter504 is thereafter withdrawn further and finally from the patient. Asshown in FIG. 19 d, the anchoring means 54 has been deployed inside theascending aorta 33 and the apparatus 42 is completely deployed.

Referring now to FIGS. 20 a-e, methods for introducing an apparatus 42into the inferior vena cava 4 and the superior vena cava 2,respectively, will be described. In FIG. 20 a, an access route to theinferior vena cava 4 is indicated. A puncture is made in the neck of thepatient to access the internal jugular vein 7. A guide wire 508 ispassed through the internal jugular vein 7 into the superior vena cava 2and the right atrium 6 and further into the inferior vena cava 4. Therestraining catheter 504 and the apparatus 42 are introduced inside thedelivery catheter (not shown) such that the restraining catheter 504extends into the inferior vena cava 4. As shown in FIG. 20 b, therestraining catheter 504 is retracted such that the anchoring means 54is released inside the inferior vena cava 4 for fixing the position ofthe apparatus 42. The restraining catheter 504 is thereafter withdrawnfurther and finally from the patient. As shown in FIG. 20 c, the valvemeans 52 has been deployed inside the inferior vena cava 4 and theapparatus 42 is completely deployed.

The same access route may be used for placing an apparatus 42 in thesuperior vena cava 2. The restraining catheter 504 and the apparatus 42are introduced into the superior vena cava 2. The restraining catheter504 is retracted such that the valve means 54 is released inside thesuperior vena cava 2, as shown in FIG. 20 d. The restraining catheter504 is withdrawn further and finally from the patient. As shown in FIG.20 e, the anchoring means 54 is deployed inside the superior vena cava 2and the apparatus 42 is completely deployed. If the groin access to thefemoral vein is used, an apparatus 42 would first be deployed in thesuperior vena cava 2 and an apparatus 42 would secondly be deployed inthe inferior vena cava 4 using an identical method.

It should be emphasized that the preferred embodiments described hereinis in no way limiting and that many alternative embodiments are possiblewithin the scope of protection defined by the appended claims. Forexample, the different embodiments of the valve means and the anchoringmeans may be combined in any manner. Further, it would be apparent to aperson skilled in the art, that other veins or arteries may be chosen inorder to obtain access to the large vessels around the heart and to thedifferent chambers of the heart.

1. A prosthesis for improving blood flow through a native heart valvewithin a heart comprising: an anchoring framework configured to engagetissue associated with the heart and thereby anchor the prosthesis; anda valve member coupled to the anchoring framework and extending from theanchoring framework so as to be interposed between leaflets of thenative heart valve when the anchoring framework is engaged with thetissue; wherein the valve member has an expanded configuration forcontacting at least one leaflet of the native heart valve during a firstdirection of blood flow and the valve member has a contractedconfiguration for releasing contact with at least one leaflet of thenative heart valve during a second direction of blood flow.
 2. Theprosthesis of claim 1, wherein the anchoring framework comprises atissue engagement structure configured to engage ventricular tissue inthe heart.
 3. The prosthesis of claim 2, wherein the anchoring frameworkfurther comprises a connecting member for coupling the valve member tothe tissue engagement structure.
 4. The prosthesis of claim 1, whereinthe anchoring framework is a stent configured for deployment in a bodylumen.
 5. The prosthesis of claim 1, wherein the valve member isexpandable in a direction transverse to the flow of blood for preventingregurgitation through the native heart valve.
 6. The prosthesis of claim1, wherein the valve member comprises an umbrella-shaped flexible flap.7. The prosthesis of claim 6, wherein the anchoring framework includesan elongated rod extending through a center region of theumbrella-shaped flap.
 8. The prosthesis of claim 7, further comprising aplurality of flexible connecting members extending from a peripheraledge of the umbrella-shaped flap and the anchoring framework.
 9. Anapparatus for restoring function to a mitral valve in a human heart,comprising: a flow control member; and an anchor having a first end anda second end, the first end of the anchor being connected to the flowcontrol member, the second end of the anchor having a tissue engagementstructure, the anchor having a length such that the flow control memberis positioned at least partially within the mitral valve when the tissueengagement structure is engaged with the tissue; wherein the flowcontrol member is movable between an expanded state to contact at leastone leaflet of the mitral valve and thereby substantially prevent bloodflow past the mitral valve and a reduced state to thereby allow bloodflow past the mitral valve.
 10. The apparatus of claim 9, wherein theanchor is elongated between the first and the second ends.
 11. Theapparatus of claim 10, wherein the flow control member is a flexibleumbrella-shaped flap.
 12. The apparatus of claim 11, further comprisinga plurality of connecting threads extending from a circumference of theumbrella-shaped flap to the anchor.
 13. The apparatus of claim 9,wherein the tissue engagement structure includes a framework of strutsengageable with an interior surface of the heart.
 14. The apparatus ofclaim 13, wherein the tissue engagement structure comprises a pluralityof hooks.
 15. A method for restoring function to a heart valve in ahuman heart, comprising: introducing a prosthesis into an interior ofthe heart; securing one end of the prosthesis to tissue within theheart; positioning an opposite end of the prosthesis between opposingleaflets of the heart valve; expanding the prosthesis so as to place theprosthesis into contact with at least one leaflet of the heart valve andthereby substantially prevent blood flow through the heart valve in afirst direction; and contracting the prosthesis so as to substantiallyallow blood flow through the heart valve in a second direction.
 16. Themethod of claim 15, wherein the securing of one end of the prosthesis inthe heart includes extending the one end of the prosthesis at leastpartially through heart tissue in a left ventricle.
 17. The method ofclaim 15, wherein expanding the prosthesis to contact at least oneleaflet of the heart valve includes coapting at least one leaflet of theheart valve with the prosthesis.
 18. The method of claim 15, whereinexpanding the prosthesis to contact at least one leaflet of the heartvalve includes expanding an umbrella-like flexible flap disposed at oneend of the prosthesis.
 19. The method of claim 18, further comprisingsecuring a periphery of the flexible flap to the prosthesis with aplurality of flexible connecting members extending between the peripheryof the flexible flap and the prosthesis.
 20. The method of claim 18,wherein the contracting the prosthesis to substantially allow blood flowincludes allowing the umbrella-like flexible flap to collapse.